Pneumonia Flashcards
What is the pathogen and type of pneumonia associated with Porcine pleuropneumonia?
Actinobacillus pleuropneumonia
fibrinous bronchopneumonia with extensive pleuritis
What type of pneumonia is associated with Canine distemper virus? What cells does this virus like?
Interstitial pneumonia Epithelial cells (type I pneumocytes)
What type of pneumonia is associated with Equine herpes virus?
Equine viral rhinopneumonitis
bronchointerstitial pneumonia
What is the pathogenesis for aerogenous entry pneumonia?
inhale infectious agent –> overcomes host defenses –> establish infection in cranioventral lung –> endo- and peribronchial spread within lung –> septicemia
What is the pathogenesis for hematogenous entry pneumonia?
Bacteremia, viremia, migrating metazoan parasites –> damage alveolar septum –> diffuse infection of pulmonary interstitium
what type of pneumonia is caused in Shipping Fever? What is the major pathogen responsible?
Severe fibrinous bronchopneumonia
Mannheimia haemolytica
What are the opportunistic bacteria involved in bovine enzootic pneumonia?
Pasteurella multocida Mannheimia haemotytica Arcanobacterium pyogenes Histophilus somni E. coli
Can Mannheimia haemolytica cause shipping fever on its own?
No – it is an opportunistic bacteria. It normally lives in the respiratory tract of healthy cattle.
What is the mechanism for shipping fever/ pneumonic mannheimiosis ?
Viral infection (PI3, Bo-HV1, BRSV, BVDV) or suppressed immunity in lung from stressors (shipping, weaning, crowded area, etc) –> provides entry for opportunistic bacteria Mannheimia haemolytica –> establishes in lung –> virulence factors –> kills macrophages and neutrophils along with damaging alvoli and lung tissue –> necrosis, edema, fibrin –> severe fibrinous bronchopneumonia
What is the pathogenesis for bovine enzootic pneumonia?
Viral infection (PI3, Bo-HV1, adenovirus, BRSV) or mycoplasma infection –> predisposes cattle to secondary opportunistic bacteria –> suppurative bronchopneumonia
What bacterial agents can complicate equine influenza?
Streptococcus equi
Streptococcus zooepidemicus
Streptococcus aureus
Escherichia coli
What are the clinical signs associated with equine influenza?
fever cough abnormal lung sounds (crackles and wheezes) anorexia depression
What is the pathogenesis for porcine enzootic pneumonia? What is the etiologic agent?
Mycoplasma hyopneumoniae
Decreased immune status from overcrowding, ventilation, concentrations of noxious gases, mixing of stock –> entry –> adhere to cilia of bronchi –> virulence factors –> colonize –> adhere on cilia of trachea also –> provokes influx of neutrophils into mucosa –> hyperplasia of lymphocytes in BALT –> bronchointerstitial pneumonia –> secondary infection (pasteurella multocida, arcanobacterium pyogenes, Bordetella bronchiseptica, Haemophilus, Mycoplasma) –> purulent suppurative bronchopneumonia
What gross lesions are seen with Pneumonic mannheimiosis?
fibrinous bronchopneumonia
pleuritis
interlobular edema
abscesses
What are the toxins produced by M. hemolytica and what damage do they cause?
Endotoxin –> damage endothelium –> vascular damage –> fluid leaks from vessels and some thrombosis –> lung necrosis –> abscesses, edema, pleuritis
Leucotoxin (exotoxin)–> damage macrophages, pmn –> increase production/ release of cytokines, LTs, TNF, ILs –> absorbed into bloodstream (toxemia) –> systemic illness (fever, depression, cough, nasal discharge)
